Metal pad modification

Abstract

The present invention provides a structure. In an exemplary embodiment, the structure includes a base material, at least one metal pad, where a first surface of the metal pad is in contact with the base material, and a metal pedestal, where the metal pedestal is in contact with the metal pad, where a radial alignment of the metal pad is shifted by an offset distance, with respect to the metal pedestal, such that the metal pad is shifted towards a center axis of the base material, where a first dimension of the metal pad is smaller than a second dimension of the metal pad, where the second dimension is orthogonal to a line running from a center of the metal pad to the center axis of the base material, where the first dimension is parallel to the line.

What is claimed is: 
     
       1. A structure comprising:
 a base material; 
 at least one metal pad,
 wherein a first surface of the metal pad is in contact with a surface of the base material, 
 wherein the metal pad is deposited within the base material; 
 
 a metal pedestal,
 wherein a first surface of the metal pedestal is in contact with a second surface of the metal pad, 
 wherein a radial alignment of the metal pad is shifted by an offset distance, with respect to the metal pedestal, such that the metal pad is shifted towards a center axis of the base material,
 wherein the offset distance ranges from 0 μm to 20 μm, 
 
 wherein a first dimension of the metal pad is smaller than a second dimension of the metal pad, 
 wherein the second dimension is orthogonal to a line running from a center of the metal pad to the center axis of the base material, 
 wherein the first dimension is parallel to the line running from the center of the metal pad to the center axis of the base material, 
 wherein an aspect ratio of the second dimension to the first dimension is greater than 1:1 and less than 2:1; and 
 
 a solder bump in contact with a second surface of the metal pedestal; 
 a passivation layer between the metal pedestal and the metal pad with a via in the passivation layer,
 wherein the metal pedestal contacts the metal pad through the via in the passivation layer, 
 wherein the metal pedestal is deposited on the passivation layer and the second surface of the metal pad, 
 wherein the passivation layer has a thickness ranging from 0 μm to 20 μm.